Clamping device



Sept 3, 1940. F. M. SLATER 2,213,329

CLAMPING DEVICE Filed Sept. 7, 3939 HIS ATTORNEY Patented Sept. 3, l1940 j anni TENT oFFicE CLAMPIN G DEVICE apprises@ september 7, 1939, serial No. 293,775

Claims.

This invention relates to rock drills, and more particularly to a clamping device for securing a rock drill to a support, as for example a drill column or a quarry bar.

5 One object of the invention is to facilitate the manipulation of the clamping device.

Another object is to assure firm gripping action of the clamping device on the objects which it is intended to engage.

l0 Other objects will be in part obvious and in part pointed out hereinafter.

In the drawing accompanying this specification `and in which similar reference numerals refer to similar parts,

Figure 1 is a side elevation of a rock drilling mechanism equipped with a clamping device constructed in accordance with the practice of the invention,

Figure 2 is a transverse View taken throughv Figure l on the line 2-2, and

Figure 3 is a plan view, in section, taken through Figure 2 on the line 3-3,

Referring more particularly to the drawing, 20 designates, in general, a drilling mechanism comprising an extensible mounting 2i, shown as being in the form of a drill column, and a rock drill 22 which is secured to the mounting by a clamping device 23 constructed in accordance with the practice of the invention.

The mounting 2i and the rock drill 22 may be of kno-wn types, the former, shown by way of example, comprises a cylindrical body 24 carrying a pointer 25 at its upper end for engagement with the rock surface, and in the lower end of the body 24 is a screw 2E carrying a foot piece 2l to support the mounting.

The rock drill is shown equipped with pressure fluid actuated feeding mechanism for advancing it in accordance with the penetration of the working implement 28 into the work. The

feeding mechanism illustrated accordingly comprises a cylinder 2S having guide ribs 3U for a guide shoe 3l carried by an extension 32 on the rearward end of the rock drill, and in the cyli inder 29 is a piston 33 having a rod 34 which Y jects from the free end of the trunnion 42.

In the form of the invention illustrated the clamping device 23 comprises a body 36 having a coniform bore 3l of which the surface'38 con-` stitutes a seat for a conical boss 39.' The boss 39 is lan integral portion of a rigid jaw 40 hav- 5 ing a concave surface 4l to conform with the contour of the body 2d against which it Seats. The coniform bo-re 31 is located in one side of the body 35 and on the opposite side of the body is a trunnion 112 having a bore 43 in axial align- 10 ment with the bore 3l to receive a rod M which extends entirely through the bore 43 and through an aperture 45 in the jaw lil),

The rod 44 has a threaded end vl5 which pro- The 15 opposite end 4l of the rod is ared and is provided with lugs 48 that lie within the aperture '45 and contain pins 49 that engage the ends of a flexible member 50, shown as being in the form of a chain, that encircles the body 24 20 and cooperates with the jawilll for clamping the body 25 between these elements. The rod d4 is slidable the bore 43, and on the threadedv end 46 of said rod is a nut'5l that acts against the free end ofthe trunnion 42 for drawing the 25 chain 56 into firm frictional engagement with the body 24 and for pressing the jaw fil! against` the body and the conical boss into frictional engagement with the surface 38.

In addition to its function as a support for 30 the clamping elements engaging the body 24 of the mounting, the body 36 also serves as va gripping element to secure the clamping device to the rock drill or, as in the form of the arrangement illustrated to the cylinder' 29 of 35 the feeding mechanism. To this end the body 36 is provided with a gripping portion 52 having a curved seating surface 53 shaped to conform with the surface of the cylinder 2Q, and a gripping member 5d, complementary to the-'40 gripping portion 52, is disposed on the trunnion 42 to cooperate with the gripping portion 52 for holding the cylinder 29.

The gripping member 51's is loosely slidable on the trunnion 52, having a bore 55 -of larger di- 45 ameter than the trunnion so that the gripping member will be capable of a certain degree o-f tilting movement without hindrance from the trunnion. In order that such tilting movement may be conveniently effected the kgripping meml f arm 58 on the body 36. 55

The element that actua-tes the gripping member 54 also consists of a nut 59 threaded on the free end of the trunnion i2 and acting against a seating surface Q on the gripping member. The nuts 59 and 5l, while having bores of dii-ferent; diameters, are of the same external conformation and dimensions in order to be engaged by the same actuator or wrench, thereby eliminating the necessity of having a plurality of wrenches for tightening and loosening the clamping members of the device. The actuator illustrated for this purpose and designated ti comprises an endless loop having a bore @E shaped to receive the nuts E? and 5l and having a handle Elfi integral therewith.

To the end that the actuator ti may be constantly in a convenient position for engagement with either of the nuts 5i and said actuator is normally disposed between the nuts which are spaced a suicient distance apart to provide room therefor, and on the inner end of the nut 5i is a boss 85 to form a seat-for the actuator .vhen not in use. A ange (it on the outer end of the nut 5l prevents removal of the actuator from the assembly without removing the nut 5i.

Encircling the trunnion i2 is a spring E? that seats with its ends against the gripp---g member 54 and the body 3G te remove the gripping member 54 from its gripping position upon untl'neading of the nut 59 on the trunnion 62,

In practice, whenever it is intended to attach therock drill to the mounting 2l the body 24 is l extended through the loop formed by the chain 5B. The mounting 2l is then placed in the correct position with respect to the work and the clamping device is placed in the desired position along the length of the mounting. Thereafter the nut 5l is threaded on the rod ill against the end of the trunnion i2 to draw the chain 50 and the jaw l0 tightly into engagement with the body 2li. This force will also press the conical boss S9 into firm frictional engagement with the surface 38 of the body 36. The feeding cylinder 29 of the rock drill is then inserted between the gripping member 54 and the gripping portion 52 and the nut 59 is manipulated to rock the gripping member Ell about the fulcrum 58 and into tight engagement with the cylinder 29. After the clamping elements of the device have been brought into tight frictional engagement with the body 2li and the feeding cylinder the actuator 6i is placed on the seating surface 65 until again needed.

In practice the present invention has been found to be a highly efficient device for securing a rock` drilling mechanism to its mounting. Ar-

necessitating the operator to shift his position; This is extremely desirable in devices of this character since it is necessary for the operator to support a very considerable portion of the weight of the drilling mechanism until at least the clamp engaging the mounting can be tightened.

I claim:

l. A claiinping device, comprising a body having a bearing surface, a rigid jaw having a bearing surface to engage the rst mentioned bearing surface, a ilexible member extending into the rigid jaw to cooperate with the jaw for effecting clamping action, and means for actuating the flexible member with respect to the jaw and for effective locking engagement between the bearing surfaces to lock the rigid jaw to the body.

2. A clamping device, comprising a body having an internal coniform bearing surface and a bore coaxial with the coniform surface, a rigid jaw having a conical surface to engage the bearing surface, a rod slidable in the bore, a flexible member extending into the rigid jaw to cooperate with the jaw for effecting clamping action and having its ends connected to the rod, and means for actuating the rod in the bore to move the flexible member with respect to the jaw and to press the conical surface of the jaw into frictional engagement with the coniform bearing surface.

3. A clamping device, comprising a pair of cooperative clamping members, a body to frictionally engage one of the clamping members, a hollow trunnion on the body, a rod slidable in the trunnion connected to the other clamping member, and a nut threaded on the rod and acting against the trunnion to effect clamping action of the members and to force said one clamping member into frictional engagement with the body.

4. Apparatus of the character described, comprising a pair of clamping devices, bea-ring surfaces on the clampimY devices engaging each other to permit of relative rotational movement of the clamping devices, means for effecting clamping movement of one clamping device and for preventing relative rotational movement of the bearing surfaces, means for effecting clamping movement of the other clamping device, an actuator for manipulating both means, and seat between both of said means to normally support the actuator.

5. Apparatus of the character described, comprising pair of clamping devices, coniform bearing surfaces on the clamping devices cooperating with each other to permit of relative rotational movement of the clamping devices, a nut for actuating one clamping device and for forcing the coniform bearing surfaces into firm frictional engagement with each other to preent relative rotary movement between the clamping devices, an actuator for actuating the nuts, and a seat between and directly adjacent the nuts to normally support the actuator.

FRED M. SLATER. 

